The latest generation of telecommunications systems is based on the Internet Protocol (IP) Multimedia Subsystem (IMS) network. This network which carries many different kinds of medias, including voice, video, still picture, text, and data, will be used to provide advanced telecommunications services as well as such legacy services as voice. Signals for any service will be carried using the common IMS protocol.
It is apparent that a system having the great flexibility of IMS requires a highly sophisticated charging framework and protocol. That protocol is also being defined and is called Diameter. When a Session Initiation Protocol (SIP) session is initiated, the Diameter message to a Charging Collection Function (CCF) or Charging Data Function (CDF) is invoked. The CCF/CDF receives details of the session, including an identification of the parties involved in the session, and, based on this information, prepares the data necessary to charge the appropriate parties. The specifications for the Diameter system are presented in Document 3GPP TS 32.240 which is currently in Release 6. The document is issued by the 3GPP (3rd Generation Partnership Project) Organizational Partners.
A problem of the prior art is that while this document specifies a highly flexible arrangement, there are still some areas of flexibility which are missing.
Applicants are including a Glossary of the abbreviations encountered in this application at the end of the Detailed Description.